Hairy leukaemic cell influx into the cerebrospinal fluid secondary to encephalomyelitis.

A case report of a 53 year old male with hairy cell leukaemia is presented in whom encephalomyelitis caused by toxoplasmosis resulted in an influx of hairy cells into the cerebrospinal fluid following disruption of the blood-brain barrier. These cells subsequently disappeared as the barrier reformed. It is suggested that the presence of hairy cells in the cerebrospinal fluid is a secondary self-limiting phenomenon.

Effect of haemolysate preparation on measurement of red cell folate by a radioisotopic method.

The effects of varying the method of preparation of haemolysates on the measurement of red cell folate concentration were investigated using the Simultrac kit. The concentration of ascorbic acid did not have any significant effect on the assayed concentrations of folate, but lower concentrations were obtained when the incubation time was increased. Folate was stable for 14 days in cells when they were stored at 4 degrees C and for seven days at -25 degrees C, but instability was increased by storage in ascorbic acid, by the use of stored (4 degrees C) ascorbic acid, and by preparing the haemolysates by freeze-thaw cycling.

Central and peripheral SEP defects in neurologically symptomatic and asymptomatic subjects with low vitamin B12 levels.

Somatosensory evoked potentials (SEPs) following median nerve stimulation were abnormal in 7 patients with sensory impairment due to vitamin B12 deficiency. Extensor plantar reflexes indicated a central sensory pathway lesion in 4 cases and absent tendon jerks suggested peripheral neuropathy in 4, but median nerve SEPs indicated a predominantly central lesion without marked peripheral nerve involvement in 6 and an axonal neuropathy without CNS involvement in 1. The latter had evidence of central slowing of conduction in SEPs following posterior tibial nerve stimulation.